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1.
Cheng-Jung Lin Song-Yung Wang Te-Hsin Yang Ming-Jer Tsai 《Journal of Wood Science》2006,52(4):337-341
Taiwania (Taiwania cryptomerioides Hay) is an important timber species in Taiwan. Growth in generally improved trees under intense silvicultural practice is
so rapid that rotations or the practice of thinning trees may be as short as 20–30 years. Thus, the wood properties of young
plantation trees need to be characterized to effectively use this resource. The effects of different thinning and pruning
methods on the compressive strength parallel to grain of young Taiwania trees were explored. Average compressive strengths
with various thinning treatments revealed the trend of no thinning > medium thinning > heavy thinning and in the pruning treatments
showed the trend of medium pruning > no pruning > heavy pruning. However, most results showed no statistically significant
differences among thinning and pruning treatments. 相似文献
2.
Song-Yung Wang Cheng-Jung Lin Chih-Ming Chiu Jin-Hau Chen Te-Hsin Yung 《Journal of Wood Science》2005,51(1):1-6
The effects of different thinning and pruning methods on the bending strength and dynamic modulus of elasticity (DMOE) of young Taiwania (Taiwania cryptomerioides Hay) were investigated. The average DMOE, modulus of elasticity (MOE), and modulus of rupture (MOR) in the thinning treatments showed the following trend: no thinning > medium thinning > heavy thinning. This indicates that thinning reduces average bending properties. The average DMOE, MOE, and MOR in the pruning treatments showed the following trend: medium pruning > no pruning > heavy pruning. According to this tendency, better average qualities of lumber and specimens were from wood subjected to no-thinning and medium-pruning treatments according to an ultrasonic wave technique and static bending tests. However, most results showed no statistically significant differences among thinning, pruning, and thinning and pruning treatments. The average values of DMOE, MOE, and MOR of visually graded construction-grade lumber were significantly greater than those of below-grade lumber. Moreover, there were very significant positive relationships between density, ultrasonic velocity, DMOE, MOE, and MOR, although the determination coefficients were small. 相似文献
3.
The effects of various thinning and pruning methods on the density profile and annual ring characteristics of Taiwania (Taiwania cryptomerioides Hay.) using the drilling resistance technique were investigated. The results showed that thinning caused wider annual rings
than medium thinning or no thinning, and pruning caused narrower annual rings than no pruning. Moreover, the thinning treatment
affected annual rings more effectively than the pruning treatment. The average ring density after the thinning treatments
showed a trend as follows: no thinning > medium > heavy. This indicates that thinning reduces the average ring density. The
average ring density after the pruning treatments showed a trend as follows: medium > no pruning > heavy. However, the differences
between thinning and no thinning were not statistically significant. The percentage of latewood in Taiwania after these three
thinning and pruning treatments are shown. The results with silvicultural treatments have the order: medium > not treated
> heavy, but there are no statistically significant differences among thinning, pruning, and thinning where pruning interactions
were observed. Moreover, there were highly significant negative relations between the average ring width and the various ring
densities for Taiwania, but the determination coefficients were small. In addition, there was a highly positively significant
relation between the latewood percentage and latewood width.
Received: November 22, 2001 / Accepted: May 21, 2002
Acknowledgments The authors thank the National Science Council of ROC for financial support through grant NSC-90-2313-B-002-338, and the
Taiwan Forestry Research Institute for their contribution (210).
Correspondence to:C.-J. Lin 相似文献
4.
The relationships between bending properties, compressive strength, tracheid length, microfibril angle, and ring characteristics
of 20-year-old Taiwania (Taiwania cryptomerioides Hay.) trees were examined. The trees came from different thinning and pruning treatments, but the practices showed no significant
effect on the investigated properties. The results showed that based on comparison with the literature, plantation-grown immature
Taiwania have noticeably lower average strength properties than mature trees of the same species. Wood density and bending
and compressive strengths were not related to either tracheid length or microfibril angle in young Taiwania. There were positive
relationships between bending strength and compressive strength. The wood density, ring width, earlywood width, earlywood
density, and latewood percentage were the most important predictors of strength by simple linear regressions. The wood density
and ring width/earlywood width may be considered as indicators for assessing the bending strength, while wood density and
latewood percentage were the best predictors of compressive strength by multiple linear regressions. 相似文献
5.
Chih-Ming Chiu Song-Yung Wang Cheng-Jung Lin Te-Hsin Yang Ming-Chun Jane 《Journal of Wood Science》2006,52(1):9-14
The fractometer is a device that breaks a radial increment core along the fiber for the measurement of crushing strength,
which is a direct wood quality indicator for structural lumber. In this study, the crushing strength of Taiwania (Taiwania cryptomerioides Hay) trees using the fractometer was investigated and the data were used to determine the position of demarcation between
juvenile and mature wood. Segmented regression and variance component analysis were used to estimate the demarcation position.
With increasing cambium age, the core wood improves the crushing strength in the outer wood area. Within-tree variations in
wood properties were greater than between-tree variations. In this experiment, the position of demarcation between juvenile
and mature wood occurred at an approximate distance of 10.8cm to 13.2cm from the pith at about 18–20 years of cambium age. 相似文献
6.
台湾杉、秃杉引种栽培试验及生长效果分析 总被引：3，自引：0，他引：3
通过在福建省闽清美菰林场引进台湾杉与秃杉进行育苗和造林试验,结果表明:相同或不同海拔营造台湾杉与秃杉纯林,其两种树种间或不同海拔之间的林分主要指标的生长量差异不显著。试验还表明台湾杉与秃杉是福建省高海拔山地造林较为优良的用材树种,速生期长,可以扩大造林范围。 相似文献
7.
Taiwania (Taiwania cryptomerioides Hayata), native to Taiwan, is one of the most economically important tree species grown there. In this article we summarize
the current results of phytochemistry and bioactivity of Taiwania extracts, including antifungal, antitermite, antibacterial,
and antimite activities as well as cytotoxicity against three tumor cells. The resources of Taiwania are also addressed.
Received: January 23, 2002 / Accepted: March 8, 2002
Acknowledgment The authors thank the National Science Council of R.O.C. for financial support (NSC-90-2313-B-002-344).
Correspondence to:S.-T. Chang 相似文献
8.
秃杉抚育间伐初步研究 总被引：2，自引：0，他引：2
通过对安溪县福前农场造林密度为2 505株.hm-2的9年生秃杉林分设置极强度间伐(60%)、强度间伐(40%)、弱度间伐(20%)及不间伐(对照)4个处理,间伐3 a后,调查林分胸径、树高、单株材积、蓄积量等指标,研究不同间伐强度对其生长量的影响。结果表明:不同间伐强度对林分胸径生长、单株材积、蓄积量的影响都达到显著水平,而对树高生长有一定影响,但差异不显著。综合分析表明,对9年生的秃杉林分,选择强度间伐(间伐总株数的40%)进行抚育间伐较为合适。 相似文献
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10.
通过对台湾杉和秃杉两种珍稀树种的引种栽培,就台湾杉和秃杉两种珍稀树种从种子(球果)到幼苗的整个发展过程,以及种子和苗木的生产技术做了细致的探索性研究,并就培育出的幼苗进行观察、记载和绘制成图;经定植3 a后评价引种成败。研究结果可为杉科台湾杉属的系统发育和亲缘关系方面的研究提供理论基础;也可为用材林造林、园林绿化树种提供参考和对这两种珍稀树种继续引种栽培提供实践依据。 相似文献
11.
安溪秃杉引种造林试验初报 总被引：2，自引：1，他引：1
通过对秃杉引种造林试验研究表明,秃杉具有良好的适应性、速生性和抗逆性,对幼林观测表明,其造林成活率、树高、胸径长势良好,年平均树高生长量达0.8 m、胸径生长量达1.2 cm;与福建柏、杉木生长量比较,秃杉树高提高了12%~21%、胸径提高了13%~29.8%,具有明显的增益优势,适宜作为南方用材林进一步引种栽培和推广示范。 相似文献
12.
总结了德化葛坑国有林场2009年营建的秃杉第1代无性系种子园的营建技术,并于2012年5月对建园效果进行调查分析.结果表明:砧木保存率为89.4％,嫁接保存率为86.9％,嫁接植株的正冠率为82.3％;2010年嫁接的植株平均树高、地径和冠幅分别为1.2m、3.1 cm、0.8m,最优株树高1.8m、胸径1.6 cm、冠幅1.3m. 相似文献
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14.
秃杉种源—家系联合试验表明,秃杉发芽、物候、苗期及幼林生长等11个性状中,真叶全现、一年生幼树抽高、一年生幼树全高种源间差异显著,发芽率、发芽势差异不显著;造林11年生时,种源间、家系/种源间生长性状差异显著,在遗传方差中,种源方差分量所占比例较大,种源效应最明显。选择秃杉优良种源有贵州交、贵州格、贵州昂、贵州丹、云南滕冲种源,优良种源平均单株材积遗传增益为29.68%,实际增益为34.60%。利用种源发芽、物候、苗期及幼林生长、11年生生长性状等11个性状,采用主成分分析方法,将秃杉区划为3个种源区,第1个种源区为湖北利川种源,第2个种源区包括云南昌宁、云南滕冲种源,第3个种源区包括云南龙陵、贵州丹、贵州格、贵州昂、贵州交种源,其中第3个种源区种源在广东生长表现良好,适宜在广东适生区域引种推广。 相似文献
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16.
句容低山丘陵秃杉引种试验 总被引：1，自引：0，他引：1
本场引种珍稀树种秃杉７年的试验结果表明，秃杉能适应本地生长，并以杉木适生的优良立地载植较为适宜。采用２年生无务健壮大苗深栽、壅土保墒、合理混交、适度遮萌等措施可使造林成活率达９０％以上，５年生幼树生长量达到或超过杉木，具有扩大引种的潜力。 相似文献
17.
采用不同肥料种类和施肥剂量对秃杉人工林进行施肥对比试验。观测胸径、树高和蓄积生长量,分析不同肥料种类和施肥剂量对秃杉人工幼龄林高、粗和蓄积生长量的效应。试验结果表明,合理的施肥措施对秃杉人工林生长有明显促进作用,与对照相比,年高生长增加34%,粗生长增加26%,蓄积生长增加35%。 相似文献
18.
台湾杉引种造林试验初报 总被引：1，自引：1，他引：1
台湾杉在来舟林业试验场经6年的引种造林试验表明;1年生苗高16cm,造林4年后幼林平均高2.99m,胸径3.96cm;造林初期生长较缓慢,第4年明显加快;育苗与造林技术均容易掌握,具有重要的引种价值。 相似文献
19.
秃杉混交林生产力及其对土壤肥力的影响 总被引：3，自引：0，他引：3
对秃杉檫树混交林、秃杉杉木混交林及秃杉、杉木纯林的生产力及其土壤理化性质进行研究,结果表明:秃杉混交林的生产力高于秃杉、杉木纯林,混交林中以秃杉檫树混交林的生产力最高;秃杉混交林对土壤理化性质改善作用强于秃杉和杉木纯林,秃杉檫树混交林改土效果最明显;秃杉生长速度快于杉木。 相似文献
20.
由于马尾松迹地改造不同于整地营造火力楠秃杉混交林、纯林,对幼林3年生的林木生长效果进行了对比分析。结果显示:火力楠、秃杉混交林的林木生长状况,分别均比纯林的林木生长状况良好,其树高于6.9%、34.8%,胸径粗于9.7%、30.8.%,冠宽于14.3%、16.7%。火力楠秃杉混交林的土壤肥力N、P、K,分别均大于纯林的土壤肥力N、P、K。 相似文献